Dynamic changes of facial skeletal fractures with time.

To investigate the characteristics of imaging changes with time of facial fractures, patients with facial fractures who had computed tomographic scan were enrolled including 500 patients who were divided into six groups based on the time of scanning: super early (<3 d), early (4-7 d), early-to-medium (8-14 d), medium (15-21d), medium-to-late (22d-2 months) and late stage (>2 months). The data were compared and analyzed. Forty two patients with frontal bone fractures had high-energy impact as the reason of fractures. The fracture line was clear and sharp within one week but blunt and sclerotic due to bone absorption at 2-3 weeks, and might exist for a long time. All patients had soft tissue swelling and paranasal sinus effusion at 1-2 weeks after injury. Air might gather in the adjacent soft tissues and/or intracranially within 3 days of injury if the fracture involved the frontal or other sinuses. Twelve of the 42 patients (28.6%) had intracranial hematoma, and five (11.9%) had epidural effusion. Subarachnoid hemorrhage was mostly absorbed within one week while epidural hematoma was completely absorbed over 3 weeks. Significant changes (P < 0.05) in the fracture lines, effusion of paranasal sinuses, soft tissue swelling and pneumocephalus were observed during the study period. For patients with medial orbital wall fractures, the fracture line was sharp and clear at early stages with concurrent sphenoid sinus effusion, and the fracture line became depressed 3 weeks later with disappearance of sphenoid sinus effusion. Significant changes (P < 0.05) were observed in the sharp fracture line, soft tissue swelling, sphenoid sinus effusion and smooth depression at fracture sites. For nasal fractures, the fracture line was sharp and clear at early stages with concurrent soft tissue swelling which disappeared one week later. The fracture line became smooth three weeks later. A significant (P < 0.05) difference was demonstrated in the changes of fracture line and soft tissue swelling with time. In conclusion, facial fractures have some dynamic alterations with time and identification of these characteristics may help reaching a correct clinical diagnosis with regard to fracture severity and time.